package cn.darkjrong.verification.common.utils;

import cn.darkjrong.verification.common.pojo.vo.VerificationVO;
import cn.hutool.core.codec.Base64;
import lombok.extern.slf4j.Slf4j;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.util.Random;

/**
 * 滑块验证码生成工具类
 *
 * @author Rong.Jia
 * @date 2019/12/11 21:43:22
 */
@Slf4j
public class VerifyImageUtils {

    private static int BOLD = 5;

    private static final String IMG_FILE_TYPE = "jpg";

    private static final String TEMP_IMG_FILE_TYPE = "png";

    /**
     * 根据模板切图
     *
     * @param templateFile 模板文件
     * @param targetFile   目标文件
     * @return 切图结果信息
     * @throws Exception
     */
    public static VerificationVO pictureTemplatesCut(File templateFile, File targetFile) throws Exception {

        // 模板图
        BufferedImage imageTemplate = ImageIO.read(templateFile);
        int templateWidth = imageTemplate.getWidth();
        int templateHeight = imageTemplate.getHeight();

        // 原图
        BufferedImage oriImage = ImageIO.read(targetFile);
        int oriImageWidth = oriImage.getWidth();
        int oriImageHeight = oriImage.getHeight();

        // 随机生成抠图坐标X,Y
        // X轴距离右端targetWidth Y轴距离底部targetHeight以上
        Random random = new Random();
        int widthRandom = random.nextInt(oriImageWidth - 2 * templateWidth) + templateWidth;

        // int heightRandom = 1;
        int heightRandom = random.nextInt(oriImageHeight - templateHeight);

        log.info("原图大小{} x {},随机生成的坐标 X,Y 为（{}，{}）", oriImageWidth, oriImageHeight, widthRandom, heightRandom);

        // 新建一个和模板一样大小的图像，TYPE_4BYTE_ABGR表示具有8位RGBA颜色分量的图像，正常取imageTemplate.getType()
        BufferedImage newImage = new BufferedImage(templateWidth, templateHeight, imageTemplate.getType());

        // 得到画笔对象
        Graphics2D graphics = newImage.createGraphics();

        // 如果需要生成RGB格式，需要做如下配置,Transparency 设置透明
        newImage = graphics.getDeviceConfiguration().createCompatibleImage(templateWidth, templateHeight,
                Transparency.TRANSLUCENT);

        // 新建的图像根据模板颜色赋值,源图生成遮罩
        cutByTemplate(oriImage, imageTemplate, newImage, widthRandom, heightRandom);

        // 设置“抗锯齿”的属性
        graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
        graphics.setStroke(new BasicStroke(BOLD, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL));
        graphics.drawImage(newImage, 0, 0, null);
        graphics.dispose();

        // 新建流。
        ByteArrayOutputStream newImageOs = new ByteArrayOutputStream();

        // 利用ImageIO类提供的write方法，将bi以png图片的数据模式写入流。
        ImageIO.write(newImage, TEMP_IMG_FILE_TYPE, newImageOs);
        byte[] newImagebyte = newImageOs.toByteArray();

        // 新建流。
        ByteArrayOutputStream oriImagesOs = new ByteArrayOutputStream();

        // 利用ImageIO类提供的write方法，将bi以jpg图片的数据模式写入流。
        ImageIO.write(oriImage, IMG_FILE_TYPE, oriImagesOs);
        byte[] oriImageByte = oriImagesOs.toByteArray();

        VerificationVO verificationVO = new VerificationVO();
        verificationVO.setOriginalImage(Base64.encode(oriImageByte));
        verificationVO.setSlidingImage(Base64.encode(newImagebyte));
        verificationVO.setXWidth(widthRandom);
        verificationVO.setYHeight(heightRandom);

        return verificationVO;
    }

    /**
     * 添加水印
     * @param oriImage 图片
     */
    private static BufferedImage addWatermark(BufferedImage oriImage) {

        Graphics2D graphics2D = oriImage.createGraphics();

        graphics2D.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
                RenderingHints.VALUE_INTERPOLATION_BILINEAR);

        // 设置水印文字颜色
        graphics2D.setColor(Color.BLUE);

        // 设置水印文字
        graphics2D.setFont(new java.awt.Font("宋体", java.awt.Font.BOLD, 50));

        //设置水印文字透明度
        graphics2D.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, 0.5f));

        // 第一参数->设置的内容，后面两个参数->文字在图片上的坐标位置(x,y)
        graphics2D.drawString("zhoujin@qq.com", 400, 300);
        graphics2D.dispose();

        //释放
        return oriImage;
    }

    /**
     * 切图
     * @param oriImage      原图
     * @param templateImage 模板图
     * @param newImage      新抠出的小图
     * @param x             随机扣取坐标X
     * @param y             随机扣取坐标y
     * @throws Exception
     */
    private static void cutByTemplate(BufferedImage oriImage, BufferedImage templateImage, BufferedImage newImage, int x, int y) {

        // 临时数组遍历用于高斯模糊存周边像素值
        int[][] martrix = new int[3][3];
        int[] values = new int[9];

        int xLength = templateImage.getWidth();
        int yLength = templateImage.getHeight();
        // 模板图像宽度
        for (int i = 0; i < xLength; i++) {
            // 模板图片高度
            for (int j = 0; j < yLength; j++) {
                // 如果模板图像当前像素点不是透明色 copy源文件信息到目标图片中
                int rgb = templateImage.getRGB(i, j);
                if (rgb < 0) {
                    newImage.setRGB(i, j, oriImage.getRGB(x + i, y + j));

                    // 抠图区域高斯模糊
                    readPixel(oriImage, x + i, y + j, values);
                    fillMatrix(martrix, values);
                    oriImage.setRGB(x + i, y + j, avgMatrix(martrix));
                }

                // 防止数组越界判断
                if (i == (xLength - 1) || j == (yLength - 1)) {
                    continue;
                }
                int rightRgb = templateImage.getRGB(i + 1, j);
                int downRgb = templateImage.getRGB(i, j + 1);

                // 描边处理，,取带像素和无像素的界点，判断该点是不是临界轮廓点,如果是设置该坐标像素是白色
                if ((rgb >= 0 && rightRgb < 0) || (rgb < 0 && rightRgb >= 0) || (rgb >= 0 && downRgb < 0)
                        || (rgb < 0 && downRgb >= 0)) {
                    newImage.setRGB(i, j, Color.white.getRGB());
                    oriImage.setRGB(x + i, y + j, Color.white.getRGB());
                }
            }
        }
    }

    private static void readPixel(BufferedImage img, int x, int y, int[] pixels) {
        int xStart = x - 1;
        int yStart = y - 1;
        int current = 0;
        for (int i = xStart; i < 3 + xStart; i++)
            for (int j = yStart; j < 3 + yStart; j++) {
                int tx = i;
                if (tx < 0) {
                    tx = -tx;

                } else if (tx >= img.getWidth()) {
                    tx = x;
                }
                int ty = j;
                if (ty < 0) {
                    ty = -ty;
                } else if (ty >= img.getHeight()) {
                    ty = y;
                }
                pixels[current++] = img.getRGB(tx, ty);

            }
    }

    private static void fillMatrix(int[][] matrix, int[] values) {
        int filled = 0;
        for (int i = 0; i < matrix.length; i++) {
            int[] x = matrix[i];
            for (int j = 0; j < x.length; j++) {
                x[j] = values[filled++];
            }
        }
    }

    private static int avgMatrix(int[][] matrix) {
        int r = 0;
        int g = 0;
        int b = 0;
        for (int i = 0; i < matrix.length; i++) {
            int[] x = matrix[i];
            for (int j = 0; j < x.length; j++) {
                if (j == 1) {
                    continue;
                }
                Color c = new Color(x[j]);
                r += c.getRed();
                g += c.getGreen();
                b += c.getBlue();
            }
        }
        return new Color(r / 8, g / 8, b / 8).getRGB();
    }

}